Embolic material for endovascular occlusion of abnormal vasculature and method of using the same

Abstract

The present invention is an endovascular embolic composition. The embolic composition comprises a hydrophilic insoluble matrix having a microscopic mesh-like structure. The voids or intricacies of the matrix enclose droplets of aqueous solution as well as liquid oil. This structure is essentially equivalent to a "gel" structure with the insoluble matrix including both aqueous and oil droplets within its mesh. In creating the matrix a liquid oil base is mixed with an aqueous solution of a matrix base. The matrix base comprises an organic polymer such as a protein like albumin or its equivalent dissolved in an aqueous solution which may contain additional solutes. The matrix base solution is mixed and emulsified with the liquid oil base at a volume ratio ranging between about 1-to-1 and 1-to-5 respectively. To create the embolic composition the matrix base is then precipitated or cross-linked to form a gel with a mesh-like microscopic structure in which insoluble matrix surrounds and entraps both aqueous fluid and liquid oil. Preferably sclerifying agents are included within the composition so that scar tissue will develop to permanently occlude the embolized vasculature.

We claim: 
     
       1. An injectable embolic material for occlusion of vascular elements and fallopian tubes produced by the process comprising the steps of: preparing an aqueous matrix base comprising an aqueous solution of a matrix material capable of forming an insoluble matrix mesh;   making an emulsion of the matrix base and a liquid oil base; and   treating the emulsion to form an insoluble matrix mesh from the soluble matrix base, the insoluble matrix mesh forming a microscopic porous structure with the liquid oil base and the aqueous solution enclosed in intricacies thereof.   
     
     
       2. The embolic material of claim 1, wherein the emulsion is formed into particles prior to formation of the insoluble matrix. 
     
     
       3. The embolic material of claim 1, wherein the matrix material is selected from the group consisting of albumin, gelatin, fibrinogen, lactoglobulin, immunoglobulin, actin, and acrylamide. 
     
     
       4. The embolic material of claim 1, wherein the aqueous matrix base further includes a medicament. 
     
     
       5. The embolic material of claim 4, wherein the medicament is a sclerosant. 
     
     
       6. The embolic material of claim 1, wherein the aqueous matrix base further includes a water soluble radio-opaque material. 
     
     
       7. The embolic material of claim 1, wherein the liquid oil base comprises a radio-opaque oil. 
     
     
       8. The embolic material of claim 1, wherein the insoluble matrix is formed by heating the emulsion to precipitate the matrix material. 
     
     
       9. The embolic material of claim 1, wherein the insoluble matrix is formed by an enzymatic reaction involving the matrix material. 
     
     
       10. The embolic material of claim 1, wherein the insoluble matrix is formed by a chemical polymerization reaction involving the matrix material. 
     
     
       11. The embolic material of claim 1 further comprising an insoluble radio-opaque material. 
     
     
       12. An improved embolic material of the type used to occlude vascular elements and fallopian tubes by injection therein, wherein the improvement comprises employing a semi-solid/semi-liquid material in which a matrix base is insolubilized to entrap an aqueous solution and a liquid oil base. 
     
     
       13. The improved embolic material of claim 12, wherein the liquid oil base is radio-opaque. 
     
     
       14. The improved embolic material of claim 12, further comprising a sclerosant for encouraging formation of scar tissue in the occluded lumens. 
     
     
       15. An injectable embolic material for occlusion of vascular elements and fallopian tubes produced by a process comprising the steps of: preparing an aqueous matrix base comprising an aqueous solution containing fibrinogen; adding a sufficient concentration of calcium and thrombin to ensure enzymatic conversion of the fibrinogen to the aqueous matrix base;   making an emulsion of the matrix base and a liquid oil base; and   allowing the emulsion to react enzymatically so that an insoluble microscopic fibrin mesh is created, the insoluble fibrin mesh forming a semi-liquid/semi-solid material with the aqueous solution and the liquid oil base enclosed in intricacies of the fibrin mesh.   
     
     
       16. An embolic material used to occlude vascular elements and fallopian tubes, comprising a semi-liquid/semi-solid material wherein a water insoluble microscopic mesh of fibrin entraps an aqueous solution and a liquid oil. 
     
     
       17. The embolic material of claim 16, wherein the aqueous solution further includes a medicament. 
     
     
       18. The embolic material of claim 17, wherein the medicament is a sclerosant. 
     
     
       19. The embolic material of claim 16, wherein the aqueous matrix base further includes a water soluble radio-opaque material. 
     
     
       20. The embolic material of claim 17, wherein the liquid oil base comprises a radio-opaque oil.